4

Manual Reset Input forces RESET to assert when pulled below 0.8V.

An internal pull-up current of 250

µA on this input forces it high when left

floating. This input can also be driven from TTL or CMOS logic.

Primary supply input, +5V.

IC ground pin, 0V reference.

Power fail input. Internally connected to the power fail comparator

which is referenced to 1.25V. The power fail output (PFO) remains

high if PFI is above 1.25V. PFI should be connected to GND or VOUT

if the power fail comparator is not used.

Power fail output. The power fail comparator is independent of all other

functions on this device.

Watchdog input. The WDI input monitors microprocessor activity, an

internal watchdog timer resets itself with each transition on the

watchdog input. If the WDI pin is held high or low for longer than the

watchdog timeout period, WDO is forced to active low. The watchdog

function can be disabled by floating the WDI pin.

No Connect

RESET is asserted if either VCC goes below the reset threshold or by a

low signal on the manual reset input (MR). RESET remains asserted

for one reset timeout period (200ms) after VCC exceeds the reset

threshold or after the manual reset pin transitions from low to high. The

watchdog timer will not assert RESET unless WDO is connected to

MR.

Output for the watchdog timer. The watchdog timer resets itself with

each transition on the watchdog input. If the WDI pin is held high or

low for longer than the watchdog timeout period, WDO is forced low.

WDO will also be forced low if VCC is below the reset threshold and

will remain low until VCC returns to a valid level.

RESET is the compliment of RESET and is asserted if either VCC goes

below the reset threshold or by a low signal on the manual reset input

(MR). RESET is suitable for microprocessors systems that use an

active high reset.

Pin No.

MIC705

MIC707

Pin Name

MIC706

MIC708

MR

11

VCC

22

GND

33

PFI

44

PFO

55

WDI

6

N/A

N/C

N/A

6

RESET

77

WDO

8

N/A

RESET

N/A

8

Pin Functions

MIC705/6/7/8

µP Supervisory Circuits